So I was looking for trailer wiring for my 2013 Sport and found that it looks like just a pigtail and a 7 way. I could not find anyone who had done their own wiring so here it is. In 2010-2012 the harness also included the module but 2013 the harness is simplified. So instead of 135$ for the factory harness I picked up pn#43374 from Etrailer for 25$ and pinned out the Rovers harness and wired it in. Easy peasy. This gives you a 4 way and a 7 way plug. also probably fits other models too...
Here are the steps and instructions in short.
1. Easiest to remove the rear bumper cover.
2. Driver side under the cover are 2 plugs with blanking caps (wires in but no wires out) pretty noticeable.
3. I cut the 7 wires off from the plugs.
4. Feed the 7 way connector into place and install mounting screws (PN#43374 is a direct bolt in to the factory location)
5. Cut off the 2 connectors from the 7 way
6. Wiring is as follows: (there are only 2 that are different colors)
White goes to white (Ground)
Red on car goes to black (Power 12v)
Blue goes to blue (trailer brakes)
Yellow goes to yellow (left turn signal)
Green goes to green (rt turn singal)
Brown goes to brown (tail lights)
Yellow with (brown or purple) stripe goes to purple (reverse lamps)
7. I soldered and shrink tubed it all together but simple but end connectors will suffice.
8. Zip tied harness up and reinstall the rear bumper cover.
Its about that easy and a cheaper alternative. I know its not a lot of money but when i saw the harness it just looked obvious that it was just a pigtail and intrigued me to see if it was.